In many fields of human endeavor it is known that a collection of individuals working together as a team are able to accomplish more work, more efficiently, than the same number of individuals performing the same tasks on an individual rather than a team basis. However, teamwork is a learned skill, both in terms of the general group behaviors required to function well as a team, and also in terms of the individual behaviors required in any specific team function. Teaching a group of individuals to perform at a maximum as a team requires specific training programs. In many instances physical-conditioning endeavors may be useful in teaching teamwork skills. There is always a continuing demand for methods and apparatus for teaching teamwork skills to groups of individuals.
Likewise, there is a wide demand for devices that aid in physical conditioning. While there are many hundreds of exercise machines on the market, there is always a demand for new strength training apparatus.
Human-powered vehicles may be used to teach teamwork skills, provide strength training, and to provide other tangible benefits. Human power may be used for many different purposes. These range from human-powered modes of transportation such as bicycles and the like, to human-powered apparatus used to generate secondary power such as emergency electrical generation equipment. The efficiency with which human power is converted to mechanical power can be measured in many different ways. For example, the efficiency with which a mechanical device, such as a bicycle, converts human power (measured in, for instance, wattage output) to mechanical power can be measured and quantified fairly easily and accurately. But as mechanical design takes into account principles of ergonomics, mechanical devices tend to be more "user friendly" and comfortable, which also makes their use more efficient. This is a more subjective but no less important measure of the "efficiency" of a power-converting device. But regardless of what yardstick is used to measure efficiency, it is true that the more efficiently human power output is translated into mechanical output, the less work the human has to perform to generate mechanical power.
Human-powered vehicles such as bicycles and many less traditional human-powered vehicles offer many benefits to their users. For instance, not only can such vehicles provide an efficient mode of transportation, but they can also be enjoyable as recreational devices. As energy resources, such as petrochemicals that are used to power internal combustion engines, become more and more scarce, alternate sources of transportation become more important. And the problems associated with environmental pollution need no explanation. Human-powered vehicles thus solve many of the problems associated with vehicles powered by internal combustion engines. There will always be a demand, therefore, for efficient and enjoyable vehicles that are powered by the people who ride them.
There are many, many types of bicycles and other human-powered vehicles. While most are designed for one or at most two riders, some have been designed for use by four and even more riders. But not all people who would like to use alternate transportation methods can ride bicycles. One example of a non-traditional human powered vehicle is described in U.S. Pat. No. 4,700,962. In the device disclosed in this patent, a rider's motion simulating rowing propels the vehicle described in this patent. The rowing motion applied to handles and a seat that moves longitudinally along a rail is translated through a chain and elastic cord arrangement into rotational motion that drives wheels. Directional control is supplied to a control wheel that is turned by lateral, side to side motion of the rider, which turns the control wheel with cables routed through various pulleys.
Yet another alternate vehicle that uses a rowing motion to provide rotational movement to drive wheels is illustrated in U.S. Pat. No. 5,536,029. The device of this invention uses a pair of reciprocating arms to power a drive mechanism. The arms are also coupled to a steering linkage such that they are used to steer the vehicle by tilting laterally from side to side.
While the vehicles described in these patents provides for forward motion as a result of a rowing motion, the vehicles are adapted for only one occupant and the drive mechanisms are fairly traditional.
The present invention relates to a wheeled vehicle that in a preferred embodiment is powered solely by its occupants, and which offers multiple advantages over known human-powered vehicles such as those described above. First, because only its riders, like bicycles may power the invention, it provides an alternative form of transportation compared to traditional vehicles that are powered by engines such as internal combustion engines. But unlike most bicycles, the vehicle of this invention allows for plural participants to combine their power output. Second, because in a preferred embodiment the vehicle needs no engine (other than the riders), the vehicle is non-polluting and relies only upon its riders for a power source rather than independent fuel sources. Third, because the occupants are able to propel the vehicle more efficiently when they work together as a team, the invention serves as a highly effective training apparatus that teaches behaviors that are necessary to effective group activity. Fourth, the invention provides an efficient method of providing physical conditioning.
The invention takes into account the fact that not all riders are physically capable of outputting the same amount of power. As such, each participant may contribute to the team effort according to his or her individual abilities. The power output of each participant is coupled with the power output by the others to provide efficient power pulses. Regardless of whether the vehicle uses the power of two, three, four or more occupants, each occupant participating in driving the vehicle typically must exert physical exercise, although even when one or more participants is participating passively the vehicle utilized that participant's mass to the benefit of the remaining team members. The invention is thus a strength and physical fitness-training device. Finally, the invention is an efficient means of ground transportation that relies upon novel mechanical features for efficient propulsion and control.